Triple action press



8 Sheets-Sheer?l 1 l uur Filed Jan. 14, 1950 Oct. 8, 1957 V, GEORGEFF 2,808,798

TRIPLE ACTION PRESS Filed Jan. 14, 1950 l 8 Sheets-Sheet 2 .'204 F- E 7 Zoo INVENTQR. Wis/L' G50/@EFF HTTR/VEY @cio 8, 1957 v, GEORGEFF 2,808,798

TRIPLE ACTION PRESS Filed Jan, 14, 1950 8 Sheets-Shea?I 3' F1. E J7-j A NVENTOR. V475@ GfgoefF/f v. GEORGEFF TRIPLE ACTION PRESS 8 Sheets-Sheet 4 INVENTGRQ M75/L GEOQGEFF BY rf Filed Jan., 14, 1950 @et 8, 1957 v. GEORGEFF TRIPLE: ACTION PRESS 8 Sheets-Sheet 5 Filed. Jan. 14, 1950 INVENTUR. Vas/z. GeoQEF/f 8 Det., 8 l957 v. GEORG'EFF 2,808,798

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IAWENTOR VAS/L CSEOPGEFF BY l Haired States Patent Oilice 2,808,798 Patented Oct. 8, 1957 TRIPLE ACTION PRESS Vasil Georgel, Chicago, Ill., assignor to Danly Machine Specialties, Inc., Chicago, Ill., a corporation of lilinois Application January 14, 1950, Serial No. 138,687

6 Claims. (Cl. 113-38) My invention relates to a triple action press and more particularly to a triple action power press of improved and flexible design.

In power presses for producing work having reentrant curves, a triple action press is required. The first action operates a blank holder positioning the work. A drawing slide carrying a suitable die then forms the work, after which a third action performs an operation on the work. In the conventional triple action presses of the prior art, the construction is such that the work is upside down and must be handled to reverse the finished piece. Then too, the drawing stroke of the prior art is such that it starts at a high speed and then slows down as it approaches dead center. This limits the amount of the deformation. Furthermore, the high initial speed of the draw produces a stress which tends to tear or wrinkle the stock. ln conventional presses the variation in the amount of the draw is quite limited in a given press.

One object of my invention is to provide a triple action press in which the work is handled in its correct position so that it need not be again handled to reverse it for subsequent operations.

Another object of my invention is to provide a triple action press in which the draw is started at a slow speed and then after the metal starts to ow continues to draw at a more rapid rate.

Another object of my invention is to provide a triple action press in which a faster -overall operation may be obtained.

Another object of my invention is to provide a triple action press having an adjustable stroke on the drawing slide which may be varied within wide limits in a simple, convenient and expeditious manner in order that the draw may start at the desired slow speed for various depths of draw.

Another object of my invention is to provide a floating bed for the blank holder, to provide for ease in adjusting the press, to reduce any tendency to tear and to compensate automatically for variations in stock thickness.

Another object of my invention is to provide a triple action press of reduced size and cost for a given length of draw.

Other and further objects of my invention' will appear from the following description:

In the accompanying drawings which form part of the instant specification and which are to be read in conjunction therewith, and in which like reference numerals are used to indicate like parts in the Various views:

Fig. 1 is a sectional elevation of a triple action press containing one embodiment of my invention.

Fig. 2 is a sectional view drawn on an enlarged scale of the upper portion of the press shown in Fig. l taken along the line 2 2 thereof.

Fig. 2A is a sectional view drawn on an enlarged scale of the lower portion of the press shown in Fig. l, taken along the line 2 2 thereof.

Fig. 3 is a sectional plan view drawn on an enlarged scale taken along the line 3-3 of Fig. l.

Fig. 4 is a sectional plan view drawn on an enlarged scale taken along the line 4-4 of Fig. 1.

Fig. 5 is a sectional elevation drawn on an enlarged scale taken along the line 5-5 of Fig. l.

Fig. 6 is a sectional view drawn on a reduced scale taken along the line 6-6 of Fig. 5.

Fig. 7 is a set of curves showing the cycle of operations and the phase relationships of the blank holder, the drawing slide and the third action slide.

Fig. 8 is a diagrammatic view showing the position of parts when the blank holder ring has engaged the lower blank holder ring and clamped a workpiece therebetween.

Fig. 8A is a diagrammatic view showing the position of the parts during the operation of the drawing slide.

Fig. 8B is a diagrammatic View showing the position of parts during the operation of the third action.

Fig. 8C is a view showing the position of parts after the work has been completed and the drawing slide is moving away.

Figure 9 is a fragmentary detailed view drawn on an enlarged scale showing the floating bed support.

Figure 10 is a fragmentary perspective view of a controller for timing the engagement and disengagement of the clutch for the drawing slide.

Figure 1l is a development showing the arrangement of the conducting segments in the controller of Figure 10.

Figure 12 is a diagrammatic view showing the electrical circuits controlled by the controller shown in Figures l0 and ll.

Referring now to Fig. 1, a press frame 10 may be of any suitable construction and is shown as a straight-sided press held in assembled position by tie rods 12. Pedestal members 14 are adapted to support the press from any suitable foundation (not shown). A blank holder 16 is adapted to be reciprocated in the frame and acts against a bed 17. The bed is supported by a plurality of pistons 18 resting on diaphrarns 20 covering cylinders 22, into which uid pressure is introduced through pipe 21, thereby making the bed a oating bed and giving it a limited upward and downward movement. The blank holder 16 is adapted to be reciprocated from a pair of rocker shafts 24. Each of the rocker shafts is provided with a crank 26 secured thereto. The crank 26 is connected by link 2S to a strap 30 positioned about eccentric 32 of the eccentric gear 34 which is mounted for rotation about shaft 36. The eccentric 32 is also adapted to reciprocate the pitman 38 to reciprocate the third action slide 4l) with simple harmonic motion. Each of the rocker shafts 24 is provided with a pair of rocker cranks 42. The drawing slide 16 is supported from shaft 44 through a pair of toggle links 46 and 48. The upper link 46 is pivoted about shaft 44. The lower link 48 is pivoted about pin 50. The two toggle links are pivoted around a pin 52 to form a knee. A link 54 extends between pin 52 and a pin S6 carried by the end of each of the rocker cranks 42. It is understood, of course, that there are four drive connections to the drawing slide as can readily be seen by reference to Fig. 3, in which both rocker cranks 42 operated by the cranks 26 are shown. The action is such that as the rocker shafts'24 are oscillated through their connecting links 28 that the drawing slide will be reciprocated. The rotary nuts 58 driven in unison from shaft 60 are adapted to make a slide adjustment for the drawing slide 16.

The third action slide 40 is driven through a pair of pitmans 38 from the eccentrics 32 which are carried by eccentric gears 34 and 62. An adjustment for the third action slide 4t) is made by a shaft 64 which drives a nut 66 coacting with screw 68 through a slide adjustment motor 70. A motor, a portion of which 72 is shown in Fig. 1, is mounted on a motor platform 74 and constantly drives a flywheel 76 through an appropriate drive such as V-belts 78. The flywheel is carried by a shaft and is adapted to be clutched thereto and unclutched therefrom, as is well known in the art. The shaft 80 carries apinion 82 meshing with a gear 84. The gear 84 meshes with a coacting gear 86. The gear 84 is secured to a shaft 88 for rotation therewith. The gear 86 is secured to a shaft 90 for rotation therewith. The shaft 88 carries a pinion 92 which meshes with eccentric gear 62. The shaft 90 carries a pinion 94 secured thereto and this pinion meshes with the eccentric gear 34. Normally a brake sets the shaft 80 and immobilizes the gear train. When the clutch is clutched to the flywheel and the brake is simultaneously released, the flywheel will rotate the pinion 82 and drive the gear trainsv to reciprocate both the blank holder and the third action slide in a predetermined phase relation, as will be hereinafter more fully pointed out.

The drawing slide is operated by a linkage termiF nating in two pairs of driving links 102, there being four points through which the drawing slide 100 is driven. The upper end of each of the links 102 is secured to the slide 100 through an adjustable connectionbyI means of pins 104. These pins are carried in members 106 terminating in threaded spindles 108. Nuts 110 are adapted to be rotated by a slide adjustment shaft 112 in unison to make an adjustment of the slide 100 with respect to the pins 104. The lower ends of the driving links 102 are secured by pins 114 to bell cranks 116 pivoted about shafts 118. A pair of rocker shafts each carry a crank 122. The drawing slide is driven by a separate prime mover and its associated clutch andrbrake, as will be pointed out more fully hereinafter. The main drive shaft 123 is adapted to be clutched to a flywheel to drive a pinion 124. This pinion engages a gear 126 which meshes with a corresponding gear 12,8. The gear 123 is secured to a shaft 129 whichy carries a smaller gear 130 which meshes with an eccentric gear 140. The gear 126 is secured to a shaft` 127 which carries a smaller gear 142 which meshes with a second eccentric gear (not shown) mounted on shaft 144 for rotation in a direction opposite to the direction of the rotation of eccentric gear 140. The eccentric gear carries an eccentric 148 which is connectediby a pitman 150 to the rocker arm 122 on the left-hand rockerA shaft 120. An eccentric (not shown) isl carried by the other eccentric gear 139 shown in Fig. 4 and this is connected to a corresponding crank 150 shown in Fig. 4 secured to the right-hand rocker shaft 12,0. The construction of the pitmans and cranks is similar but sincey the two eccentric gears rotate in opposite directions the rotation of the right-hand rocker shaft 120. is equal and in the opposite direction from the rotation of the left-hand rocker shaft 1,20. Each of the rocker shafts carries la pairofcranks 152. The ends of these are connected by links 154. to the other arm of the bell crank 116. An oscillation of the rocker shafts 120 will rock. thebell cranks116 and reciprocate the drawing slide 100. It will be observed that the amplitude of the motion of'the drawing slide is governed by the angle cranks 152 make with the.links 154.

As the angle between cranks 152 and links 154approaches` 180, the oscillation of the cranks 152. will produce a small throw of the drawing slideM 100. As the cranks 152 become more horizontal a greater amplitude of motion will be imparted to the drawing slide for a given oscillation of the cranks. v

Referring now to Fig. 5, I have shown the cranks 152 and the connecting links 154. Thecranks -152 areY secured to the rocker shaft 120 by means of a plurality of splines 156. The crank 122 which is rocked by the pitman 150 is provided with a plurality of internal gear teeth 158. The rocker shaft 120 is provided with a plurality of gear teeth 160. A ring gear 162 is ,provided with both eX- ternal and internal teeth meshing with both the teeth 158 on the crank 122 and the teeth 160 on the shaft 120.

A plurality of springs 164 disposed around the ring gear normally hold the ring gear in engagement with the gear teeth on both the crank 122 and the shaft 120, thus locking the crank to the shaft. the rocker shaft 120. A plurality of pistons 168 are disposed around the crank 122 and engage the inner surface of the ring gear 162. A compressed Vfluid under pressure is adapted to be introduced through a duct 170 to move the pistons 168 to the left against the action of the springs 164. When this occurs the ring gear 162is disengaged from the internal teeth upon the crank 122 and the rocker shaft 128 may be driven through gear 166 to rotate the shaft relative to the crank 122. This will vary'the angle cranks 152 make with the links 154 and thus adjust the stroke imparted to the drawing slide when the rocker shafts are subsequently oscillated.

Referring now to Fig. 6, the gear 166 which is secured to the shaft 120 is driven through a pinion 172 whichpis secured to a shaft 174 terminating in a clutch member 176 operated by an operating member 17S and adapted to coact with clutch memberY 180carried by shaft 182. Theshaft182 is driven by. a reduction gear housed in housing 184 into which the output of an electric motor 186 is delivered through shaft 188. The gear 172 meshes with a gear 190 which meshes with a gear 192 secured to the right-hand rocker shaft 120. It will be observed that the left-hand rocker shaft 120 will be rotated by the gear 166 in a direction opposite to that in which righthand rocker shaft 120 is driven by the gear 192. Both cranks 122, that is the right-hand crank 122 and the lefthand crank 122, are simultaneously disengaged by uid pressure when an adjustment of the drawing stroke is made. The motor 186 is operated in the proper direction to adjust the stroke. After the stroke has been adjusted the springs 164 re-engage the ring gear 162 with the internal teeth 158 formed on the hub of the cranks 122. The operating member 178 is controlled by a piston rod 194 operated by a piston disposed within the cylinder 196. The arrangement is such that when iluid pressure is applied to disengage the crank 122 from the rocker shafts, the same fluid pressure will engage the clutch members 176 and 180. The motor 186 can then be operated to vary the stroke.

Referring now to Fig. 2, the flywheel 76 carries a clutch housing 200 containing a clutch plate 202 carried by the shaft 80 and adapted to be clutched to the clutch housing carried by the flywheel. The shaft 80 carries a brake member 204 securedto shaft 80 and this is simultaneously released when the clutch is set.

Referring now to Fig. 2A, ay flywheel 206 driven by a separate prime mover, such as electric motor'205, carries a clutch housing 208 adapted `to be clutched to aclutch member 210 carried by the shaft 123 when it is desired to drive the drawing slide. Brake housing 212 is carried bythe frame 10. A brake member 214 is secured to the shaft 123 and normally immobilizes this shaft. the iiywheel 206 is clutched to the shaft 123 the .brake is simultaneously released.

Referring now to Fig. 8, the work 300 is shown clamped between the upper blank holder ring 302 which is secured to the blank holder 16 and a lower blank holder ring 304 which is supported bythe bed 17. In Fig. 8A the drawing slide has moved up and carried its die 306 upwardly to perform its operation upon the work.v In Fig. 8B the third -action has moved downwardly forcing its die 308 to perform its operation While the drawing slide dwells. In Fig. 8C the drawing slide is moving downwardly while the third action and the blank holder are moving upwardly, the work having been completed.

The cycle of operations canbest be seen by reference to Fig. 7 in which the top row of figures indicates degrees of the press cycle. The curve Ais a modified sine curve showing the movement of the third.V action in simple harmonic motion.l Thisv motion is obtained by the action 0f the eccentrics 32 and the pitmans 38. Y The dotted line A gear 166 is secured to j When , bottom dead center.

curve B shows that the blank holder slide moves downwardly to about 30 of the press cycle and then dwells until about 195 of the press cycle, after which the blank holder moves upwardly until about 285 of the press cycle, whence it starts moving downwardly again. It will be observed that when the third action slide is at top dead center the blank holder is moving downwardly and is almost at bottom dead center. In the particular embodiment illustrated, the third action has a stroke of twenty inches and the blank holder has a stroke of sixteen inches. The blank holder is caused to dwell by the linkage arrangement described above. During the dwellperiod the crank 42 and the link 54 form substantially a straight angle at a time close to that when the link 46 and the link 4S form substantially a straight angle. In this manner movement of the rocker shaft will have a very small effect toward moving the blank holder during the dwell period. As will be understood by those skilled in the art, when either crank 42 and link 54 form a straight angle or when link 46 and link 48 form a straight angle there will be no movement of the blank holder. Actually there will be a very slight movement at all other times when either of the two linkages are close to a straight angle. This movement will be very small, in the nature or .005 inch, since the sine of small angles is a very small quantity. The bed against which the blank holder acts is supported by a cushion comprising pistons and the cylinders 22. Nitrogen under pressure of from 2,000 to 3,000 pounds per square inch is fed into the cylinders so that the slight movement of the blank holder during the dwell is more than compensated for by the cushion arrangement. The arrangement is such that the work will be securely clamped between the upper and lower blank holder rings during the entire working cycle. After the blank holder dwell-s the clutch of the gear train which operates the drawing slide is operated. As shown on the drawings, three curves relating to three diiferent adjustments of the drawing slide are shown. Curve C shows the cycle of the drawing slide with a four inch stroke. Curve D shows a cycle of operations of the drawing slide with an eight inch stroke, and curve E shows the cycle of operations of the drawing slide with the twelve inch stroke. With the four inch stroke the drawing slide is operated to 120 of its travel, This occurs from approximately 30 to 90 of the press cycle, the speed of operation of the drawing slide being more rapid than that of the third action. I am enabled to get a faster drawing action due to the fact that the start of the drawing movement in each case is at a comparatively slow speed of movement which accelerates until near its termination. After the drawing slide has completed its upward movement it begins to dwell due to the fact that links 102 and the upper arm of bell crank 116 form substantially a straight angle. The speed of movement of the rocker shafts, however, governing the drawing slide is so rapid that it cannot be made to dwell for a sufficient period of time to permit the third action to do its work. Accordingly, at about 120 of movement of the drawing slide for the four inch stroke and during a period of dwell the lower flywheel 206 is unclutched from its gear train so that the drawing slide will dwell, as shown by the dotted line between point C' and point C". During this dwell period the third action is moving downwardly and slightly before bottom dead center of the third action the clutch is again operated and the dwell period accomplished by the linkages between the rocker shafts and the drawing slide again resumed and the cycle of operation of the drawing slide is completed, the drawing slide moving from its upper position after the dwell to its In curve D which represents the eight inch stroke for the drawing slide the clutch is operated at point D again during a dwell period of the drawing slide and the lower flywheel is reclutched to the gear train to resume the cycle at point D during the interrupted dwell period accompli-shed by the linkages. With 6 the twelve inch stroke the driving train for the drawing slide is unclutched at point E and reclutched at point E.

The timing of the clutching and unclutching of the drawing slide to its flywheel 206 may be controlled in any appropriate manner known to the art. For example, as shown in Figures l0 to 12, a drum controller 400 is driven from the shaft S0 to rotate therewith. The drum controller contains three sets of conducting segments- 402 for the four-inch stroke, 404 for the eight-inch stroke, and 406 for the twelve-inch stroke. The conducting segments are adapted to cooperate with brushes contained in the brush and relay box 408, as is known in the art. Whenever the brushes 414 contact the conducting segment 402, a circuit will be completed through the relay winding 428 if the switch 422 is closed. Similarly, whenever the brushes 416 contact conducting segment 404 the relay winding 428 will be energized if the switch 424 is closed. Similarly, the brushes 418 are adapted to energize the winding 428 in cooperation with the conducting segments 406.

The switches 422, 424, and 420 are adapted to be selectively closed depending on the particular stroke to which the lower slide is set. Whenever the relay winding 428 is energized, its armature 430 will close the circuit across conductors 410 and 412 to energize the clutch and brake control solenoid, as is well known in the art. The energization of the clutch contro-l solenoid will engage the clutch and simultaneously release the brake.

inasmuch -as the unclutching and reclutching of the drawing slide takes place during a dwell period the time of -clutching is not critical, so that the phase relationships are not disturbed. ln other words, the drawing slide is not unclutched until it has reached its dwell period and has completed its work. lt is not reclutched except during the middle of the dwell period and at a time when the third action is nearing the completion of its work, so that it is insured that the drawing slide will remain in its upward position to permit the third action to complete its work.

As soon as the third action has completed its work and starts moving upwardly the blank holder follows, and shortly thereafter the drawing slide starts moving downwardly and continues downward movement until it reaches its bottom dead center when it is unclutched. The press cycle is determined by the third action. When it is at top dead center, the blank holder is a short distance from its closed position, so that shortly after the work has been inserted and the press started the blank holder will clamp the work and dwell, after which the drawing slide operates as described.

it will be seen that i have accomplished the objects of my invention. The work is formed in the press rightside up and must not be handled again to reverse it. The drawing action starts at slow speed and after the metal starts to flow the speed of movement is increased. This enables me to perform a faster draw overall. i have provided a simple, convenient and expeditious manner for changing the drawing stroke in a press such as shown having a twelve inch stroke on the drawing slide, a sixteen inch stroke on the blank holders and a twenty inch stroke for the third action. A conventional triple action pres-s would need a thirty inch stroke on the drawing slide, twenty-two inch stroke on the blank holder and a thirty inch stroke for the third action. in this manner I am enabled to reduce the size, weight and cost of a triple action press for performing diicult tasks and at the same time obtain flexibility. The iioating bed relieves pressure at the start of the draw, which combined with the slow movement of the drawing slide at this time eliminates the endency to tear. Furthermore, the floating bed for the blank holder furnishes an automatic compensation for variations in stock thickness. The clutching and unclutching of the drawing slide is not critical since this occurs during the dwell period and arrosage the cycle of operations will not be interrupted by minor variations in clutching times.-

lt willL be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is contemplated by and is within the scope of my claims. It is further obvious that various changes may be made in detailswithin the scope of my claims without departing from the spirit of my invention. It is,- therefore, to be under-stood that my invention is not to be limited to the specific details shown and described.

Having thus described my invention, what I claim is:

l. A triple action press including in combination a frame, a blank holder slide, a third action slide, a drawing slide, means for mounting said blank holder slide and said third action slide for reciprocationl in said frame, said third actionslide being positioned within the blank holder slide, means for mounting said drawing slide for reciprocation in said frame below said blank holder slide and said third action slide, means for continuously reciprocating said third action slide with simple harmonic motion throughout a complete cycle of press operation, toggle linkage means for reciprocating said blank holder slide in predetermined phase relation with said third action slide, a common prime mover for driving both said means, toggle linkage for reciprocating said drawing slide and a separate prime mover for driving said toggle linkage in predetermined phase relation with said third action slide, in which said means for reciprocating said third action slide with simple harmonic motion includes an eccentric, apitman extending between said eccentric and said third action slide, said toggle linkage means for reciprocating said blank holder slide includes a rocker shaft, a rocker arm secured to said rocker shaft, a connecting link between said eccentric and said rocker arm, a iirst toggle link pivotally carried by said frame, a second toggle link pivotally secured to said blank holder slide, means for pivotally connecting the ends of said toggle links at a knee, a rocker crank carried by said rocker shaft, a link connecting the end of said crank with said knee, the construction being such that both the rocker shaft crank and its connecting link and the toggle links will form straight angles at points in the cycle of the third action motion in proximity to each other and at a point in proximity to the lowermost limit of motion of said blank holder slide whereby the blank holder slide will move to closed position and dwell for a substantial part of the cycle of motion of the third action, said dwell period extending to a point in the cycle of the third action at which the third action slide reaches its bottom dead center.

2. A triple action press including in combination a frame, a blank holder slide, a third action slide, a drawing slide, means for mounting said blank holder slide and said third action slide for reciprocation in said frame, said third action slide being positioned within the blank holder slide, means for mounting said drawing slide for reciprocation in said frame below said blank holder slide and said third action slide, means for continuously reciprocating said third action slide with simple harmonic motion throughout a complete cycle of press operation, toggle linkage means for reciprocating said blank holder slide in predetermined phaserelation with said third action slide, a common prime mover for driving both said means, toggle linkage for reciprocating said drawing slide and a separate prime moverfor driving said toggle linkage in predetermined phase relation with said third action slide, in which said toggle linkage for reciprocating said drawing slide includes an eccentric, clutch means for driving said eccentric from said second prime mover, a rocker shaft, aV rocker arm, means for securing said rocker arm to said rocker shaft, a pitman extending between said eccentric and said rocker arm, afrocker crank secured to said rocker shaft, a bell crank, a link providing connection between said drawing slide and onev of the arms of saidV bell crank, a'link for connecting the end of said rocker crank to4 the`v other arm ofsaid bell crank, the construction beingv such that'` the link extending from the first bell crank arm to.v said drawingy slide and said lirst bell crank arm will form astraight anglev at substantially the same time that the link between said second bell crank arm and said rocker shaft crank willV form a straight angle. whereby -to v Y third action slide being positioned within the blank holder siide,.means for mountingsaid drawing slide for reciprocation. in said frame below said blank holder slide and said thirdv action slide, means for continuously reciprocating said third action slideV with simple harmonic motion throughout a complete cycle of press operation, toggle linkage means for reciprocating said blank holder slide in predetermined phase relationwith said third action slide, a common .prime mover for driving both said means, toggle linkage for reciprocating said drawing slide and a separate. prime mover for driving said toggle linkage in predetermined phaseV relation with said third action slide, in whichi said toggle linkage. for reciprocating said drawing slide includes an eccentric, clutch means' for driving said eccentric from said second prime mover, a rocker shaft, aA rocker arm, means for securing said rocker arm to said rocker shaft, a pitman extending between said eccentric and said rocker arm, a rocker crank secured to said rocker shaft, a bellv crank, a link providing connection between said drawing slide and one of the arms of said bell crank, a link for connecting the end of said rocker crank to the other arm `of said bell crank, the construction` being such that the linkl extending from the first bell crank arm to said drawing slide and said first bell crank arm will form a straight angle at substantially the same time that the link between said second bell crank arm and said rocker shaft crank will Yform a straight angle whereby to provide for a dwell period at the uppermost position of'travel of said drawing slide, said second prime mover being adapted to be unclutched from driving engagement withsaid eccentric during said period of dwell, said means for securing said. rocker arm to said rocker shaft comprising a ring gear .teeth formed upon said rocker shaft engaging the internal teeth of said ring gear, teeth formed upon said rocker arm engaging the external teeth of said ring gear, said. ring gear being slidably mounted for movement axially of said rocker shaft to a position out of engagement with one set of coacting gear teeth, biasing means Vnormally holding said ring gear inv engagement with both the setof teeth on the rocker arm and the set of teeth on the rocker shaft, and means for moving said ring gear to disengaging position against the actionk of said biasing means.

4. In a triple action press, a frame, a drawing slide, means for mounting the drawing slide for reciprocation in the frame, a prime mover, an eccentric, clutch means for driving the eccentric from the prime mover, a rocker shaft, a rocker arm, means for securing said rocker arm to the rocker shaft including a ring gear formed with internal and external teeth, coacting teeth formed on the rocker arm adapted to coact with the external teeth of the ring gear, teeth formed upon the rocker shaft adapted to coact with the internal teeth of the ring gear, means for mounting said ring gear for movement axially of said rocker shaft, biasing means normally holding said ring gear in engagement with both the teeth on the rocker arm and the teeth on said rocker shaft, means for moving said ring gear axially of the rocker shaft against the action of said biasing means to disengage thering gear from one ofthe coacting sets off teeth whereby selectively to freesaid rocker. arm from; the rocker shaft, Va pitman carred aanwas by said eccentric and connected to one end of said rocker arm, a rocker crank secured to said rocker shaft, a bell crank pivotally carried by said frame, a link for connecting one end of the rocker crank to one arm of said bell crank, a link for connecting the other arm of said bell crank to said drawing slide, the construction being such that said rocker crank and its connecting link will form a straight angle at substantially the same time that the second bell crank arm and its associated link form a straight angle.

5. In a triple action press as in claim 4, means for rotating said rocker shaft when the rocker arm is disconnected therefrom whereby to adjust the stroke of said drawing slide.

6. In a triple action press as in claim 4, means for rotating said rocker shaft when the rocker arm is disconnected therefrom whereby to adjust said drawing slide, said means comprising a prime mover, means including a clutch for drivingly connecting said prime mover to said rocker shaft and means operable with said ring gear disengaging means for clutching said prime mover to drive said rocker shaft.

References Cited in the file of this patent UNITED STATES PATENTS 1,633,267 Nelson June 21, 1927 1,871,088 Seidel et al. Aug. 8, 1932 2,018,576 Rode et al Oct. 22, 1935 2,071,001 Rode et al Feb. 16, 1937 2,120,356 Gla-sner June 14, 1938 2,133,444 Glasner Oct. 18, 1938 2,257,383 Iohansen Sept. 30, 1941 2,259,882 Glasner Get. 21, 1941 2,331,491 Menkin Oct. 12, 1943 2,338,352 Pague Ian. 4, 1944 2,429,062 Johansen Get. 14, 1947 FOREIGN PATENTS 450,157 Great Britain Iuly 10, 1936 

